[cs/java] handle __array__ calls similarly to TArrayDecl in CastDetect (closes #3577)

gencommon.ml

@@ -6388,6 +6388,14 @@ struct
 					in
 					let base_type = List.hd base_type in
 					{ e with eexpr = TArrayDecl( List.map (fun e -> handle (run e) base_type e.etype) el ); etype = et }
+				| TCall ({ eexpr = TLocal { v_name = "__array__" } } as arr_local, el) ->
+					let et = e.etype in
+					let base_type = match follow et with
+						| TInst(cl, bt) -> gen.greal_type_param (TClassDecl cl) bt
+						| _ -> assert false
+					in
+					let base_type = List.hd base_type in
+					{ e with eexpr = TCall(arr_local, List.map (fun e -> handle (run e) base_type e.etype) el ); etype = et }
 				| TCall( ({ eexpr = TLocal v } as local), params ) when String.get v.v_name 0 = '_' && String.get v.v_name 1 = '_' && Hashtbl.mem gen.gspecial_vars v.v_name ->
 					{ e with eexpr = TCall(local, List.map (fun e -> (match e.eexpr with TBlock _ -> in_value := false | _ -> ()); run e) params) }
 				| TCall( ({ eexpr = TField(ef, f) }) as e1, elist ) ->

tests/unit/src/unit/issues/Issue3577.hx

@@ -0,0 +1,16 @@
+package unit.issues;
+
+class Issue3577 extends Test {
+    function test() {
+        eq(testNull(2), 4);
+    }
+
+    function testNull(?x:Int=0) : Int {
+        var y:Int = x;
+        function anon() {
+            y *= 2;
+        }
+        anon();
+        return y;
+    }
+}